Aportación al estudio de arcillas expansivas asociadas a las facies garumnienses de la Conca de Tremp (Prepirineo de Lleida)

Some clay levels of the garumnian facies, which surface in the southern sector of the Tremp Basin present a principal mineralogy of expansive type. The oedometer essays show that such materials present a very high grade of potencial expansivity. The swelling pressure presents values higher than 390 KN/m2. In the majority of the areas wherw this kind of clays surface the hydric erosion phenomena and the mass movements often appear to be very common and intense. The geomorphological role of the expansive clays is discussed as the triggering factor, associated to the development of these denudative processes